<p>Environmental standards increasingly encourage water recycling in mineral processing. However, untreated recycled water often contains calcium and magnesium ions, among other species, which depress galena. One of the most important effects is the formation of precipitates that interact with the mineral surface, modifying its natural hydrophobicity. Sodium carbonate (Na₂CO₃) has been proposed to remove these ions through the formation of insoluble species. This study evaluates the interaction between galena and the solids formed during the precipitation of Ca²⁺ and Mg²⁺ with Na₂CO₃ and their influence on flotation performance. Contact angle, zeta potential, and microflotation tests were conducted to evaluate galena hydrophobicity and recovery. The results showed that calcium and magnesium strongly reduce the hydrophobicity of galena, while Na₂CO₃ treatment mitigates this adverse effect. These findings suggest that water treatment using Na₂CO₃ is a low-cost and practical strategy to improve flotation efficiency in circuits operating with recycled process water.</p> Graphical abstract <p></p>